A male fastener formed of heat treated carbon steel for high performance applications, including a shank portion, radial flange and tubular barrel, wherein the barrel has an axial length of 60% or less than the outside diameter and a fastener and panel assembly, wherein the distal open end of the barrel is deformed into an L-shape and the panel is deformed by the radial flange into an L-shape having an inwardly projecting portion deformed between the radial flange and the outwardly deformed distal end of the barrel.